At least 15 dismembered bodies have been found in two vans near Lake Chapala, south of the city of Guadalajara in western Mexico, according to police.

Jalisco state prosecutor Tomas Coronado said the count is preliminary because 15 severed human heads were found, meaning that at least that many people, but possibly more, had been cut up and put in the vans.

"The bodies are dismembered," Coronado said in an interview transcript provided by his office. He said authorities received a phone call alerting them to the presence of the vehicles on a dirt access road a few miles from Lake Chapala, which is popular with tourists and American retirees.

The two vehicles were found by the side of a highway early on Wednesday and were towed to government offices to unload the bodies.

The area has been the scene of bloody turf battles between the Jalisco New Generation gang, allied with the Sinaloa cartel, and the Zetas drug cartel.

Mexican drug cartels frequently dismember the bodies of their victims or leave them stuffed into vehicles. The gangs also frequently leave handwritten messages alongside their victims' bodies, and Coronado said that such messages were found in the vans.

"They are clearly messages between rival groups that are in conflict," he said.

Coronado said the killings may be linked to the abduction of 12 people who later escaped in the same area on Tuesday. A woman who was allegedly watching the captives was detained. She told investigators that the kidnappings were "a repercussion of what happened in Tamaulipas".

That was an apparent reference to the killings of 23 people whose bodies were found last Friday in the border city of Nuevo Laredo, in northern Tamaulipas state. The bodies were found hanging from a bridge or decapitated and dumped near city hall.

Messages were found in Nuevo Laredo threatening the Gulf cartel, which has joined Sinaloa to battle the Zetas, a gang of former Mexican special-forces soldiers. The killings could therefore be part of a wide-ranging, tit-for-tat battle between Sinaloa and the Zetas, in which both sides have been known to massacre dozens of people accused of supporting the rival gang.